Composite building panels containing laminated glass are known to those skilled in the art; these panels are often referred to as "insulating glass," and they often contain two layers of glass separated by an air space.
However, the prior art building panels generally have a relatively low insulating value.
It is an object of this invention to provide a composite building panel which has a relatively high insulating value.
It is another object of this invention to provide a composite building panel which is relatively inexpensive to produce.
It is yet another object of this invention to provide a building panel which can be decorated with a variety of different effects.
It is yet another object of this invention to provide a building panel with improved durability properties.
It is yet another object of this invention to provide a building panel equipped with heating means.
It is yet another object of this invention to provide a process for preparing the building panel of this invention.
In accordance with this invention, an insulating, substantially rectilinear, laminated building panel containing a reflective outer layer, a shatter shield bonded to the reflective outer layer, and an insulating inner layer bonded to the shatter shield, is disclosed.
The insulating layer consists of glass containing 66-75 weight percent of silica, 5-12 weight percent of calcium oxide, and 8-17 weight percent of sodium oxide; and it contains at least three evacuated chambers, each of which extends at least about 95 percent of the length of the insulating layer.